This 7950GT is cheap!
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or even this 8800!
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as for the dead card (7900GT) silly question but havce you tried plugging the monitor into each of the DVI outputs?
Also try turning thge PC off and unplugging it from the mains supply. Then wait 5 minutes or hit the power button to get rid of the remaining power, plug it back in and try again - every now and then i have to do this to get my 7900GS card to display...
hope this helps?